Wolf, if you are still with us you might look into the Iridium satellite
phones. They claim:
"Iridium Voice Services
If you work, live or travel in areas outside cellular coverage or in areas
with inadequate landline service, Iridium is for you. Eighty-six percent of
the world's landmass and all of its oceans are in areas with inadequate
landline service. Iridium addresses these situations by providing coverage
in all ocean areas, air routes and all landmasses - even the Poles. "
They claim to have polar coverage. They also have data services. Phones are
about US $650 and up at this time, with airtime in the range of $1.50 per
minute and varying monthly plan charges. But all of that is quite comparable
to what cell phones cost a decade ago. Given that this is a commercial
solution and no special licensing required, it might serve you very well. It
is possible they might also 'sponsor' comunications for your group and
reduce or absorb charges.